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Uncommon star 22 EP

42Alp Com

RA 197.4958° · Dec 17.5290° · star

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Score breakdown

· 5 badges
22 pts · Uncommon
Uncommon 34 pts → Rare
  • Naked-eye visible +8
  • Binary star +6
  • Star +3
  • Yellow-white F-type star +3
  • Main-sequence star +2
Total score 22

12 more points to reach Rare.

Badges

  • Star · +3
  • Naked-eye visible · +8
  • Binary star · +6
  • Yellow-white F-type star · +3
  • Main-sequence star · +2

Trivia

What makes it special

  • Not one star but two. It is a binary: two stars orbiting a shared centre of mass. More than half of all the 'stars' you can see are actually multiple systems.

What it actually is

  • Spectral class. Its spectrum reads F5 V — an F-type star — a little hotter, whiter and shorter-lived than the Sun.

Sense of scale

  • In perspective. Inside our stellar backyard: every radio broadcast humanity has ever made has already swept past it.

Find it in the sky

  • How to spot it. At magnitude 5.2 you can see it with your own eyes from a dark site, over in Coma Berenices.
  • Northern sky. It rides the northern half of the sky — an easier target the further north you are.
  • Best time of year. It stands highest in the middle of the night around April — that's when to go looking.

Could we get there?

  • Verdict. Hopelessly far for any craft humanity can build today.

Getting there

  • Aboard Voyager 1. ≈ 821 thousand years at Voyager 1's speed (17 km/s).

Properties

absmag
4.39
binary
yes
constellation
Com
dist ly
46.7205
luminosity
1.5276
mag
5.17
name
42Alp Com
spect
F5 V

About 42Alp Com

42Alp Com is an uncommon star. It lies about 46.7 light-years from Earth, sits in the constellation Com, shines at apparent magnitude 5.17 and has spectral type F5 V.

It is a binary: two stars orbiting a shared centre of mass. More than half of all the 'stars' you can see are actually multiple systems.

How to see it

Look for 42Alp Com in the constellation Com. At apparent magnitude 5.17, it can be glimpsed with the unaided eye under dark skies.

Like any astronomical target, 42Alp Com is best seen from a dark site away from city lights, and when it is above the horizon depends on your latitude and the time of year. The visibility panel above works out tonight's viewing window for your saved location.

Why 42Alp Com is an uncommon star

42Alp Com scores 22 points on Spacedle's rarity scale, which places it in the uncommon tier. Another 12 points would lift it into a rarer tier.

That score comes from 5 science badges — Star, Naked-eye visible, Binary star, Yellow-white F-type star and Main-sequence star — each earned for a real, measurable property of the object. Rarity on Spacedle is never random: the more remarkable an object's astrophysics, the more badges it collects, the higher it scores, and the rarer it ranks.